U.S. patent number 10,988,834 [Application Number 16/084,610] was granted by the patent office on 2021-04-27 for cr--fe--mn--ni--v-based high-entropy alloy.
This patent grant is currently assigned to THE INDUSTRY & ACADEMIC COOPERATION IN CHUNGNAM NATIONAL UNIVERSITY, POSTECH ACADEMY-INDUSTRY FOUNDATION. The grantee listed for this patent is The Industry & Academic Cooperation in Chungnam National University, POSTECH ACADEMY-INDUSTRY FOUNDATION. Invention is credited to Won-mi Choi, Sun-ig Hong, Chang-woo Jeon, Seung-mun Jung, Hyoung-seop Kim, Byeong-joo Lee, Sung-hak Lee, Young-sang Na.
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United States Patent |
10,988,834 |
Lee , et al. |
April 27, 2021 |
Cr--Fe--Mn--Ni--V-based high-entropy alloy
Abstract
The present invention relates to a high-entropy alloy especially
having excellent low-temperature tensile strength and elongation by
means of having configured, through thermodynamic calculations, an
alloy composition region having an FCC single-phase microstructure
at 700.degree. C. or higher, and enabling the FCC single-phase
microstructure at room temperature and at an ultra-low temperature.
The high-entropy alloy, according to the present invention,
comprises: Cr: 3-18 at %; Fe: 3-60 at %; Mn: 3-40 at% ; Ni: 20-80
at %: 3-12 at %; and unavoidable impurities, wherein the ratio of
the V content to the Ni content (V/Ni) is 0.5 or less.
Inventors: |
Lee; Byeong-joo (Pohang-si,
KR), Lee; Sung-hak (Pohang-si, KR), Kim;
Hyoung-seop (Pohang-si, KR), Na; Young-sang
(Changwon-si, KR), Hong; Sun-ig (Daejeon,
KR), Choi; Won-mi (Pohang-si, KR), Jeon;
Chang-woo (Suwon-si, KR), Jung; Seung-mun
(Yangsan-si, KR) |
Applicant: |
Name |
City |
State |
Country |
Type |
POSTECH ACADEMY-INDUSTRY FOUNDATION
The Industry & Academic Cooperation in Chungnam National
University |
Pohang-si
Daejeon |
N/A
N/A |
KR
KR |
|
|
Assignee: |
POSTECH ACADEMY-INDUSTRY
FOUNDATION (Pohang-si, KR)
THE INDUSTRY & ACADEMIC COOPERATION IN CHUNGNAM NATIONAL
UNIVERSITY (Daejeon, KR)
|
Family
ID: |
1000005514343 |
Appl.
No.: |
16/084,610 |
Filed: |
March 21, 2017 |
PCT
Filed: |
March 21, 2017 |
PCT No.: |
PCT/KR2017/002989 |
371(c)(1),(2),(4) Date: |
September 13, 2018 |
PCT
Pub. No.: |
WO2017/164602 |
PCT
Pub. Date: |
September 28, 2017 |
Prior Publication Data
|
|
|
|
Document
Identifier |
Publication Date |
|
US 20190055630 A1 |
Feb 21, 2019 |
|
Foreign Application Priority Data
|
|
|
|
|
Mar 21, 2016 [KR] |
|
|
10-2016-0033419 |
Mar 15, 2017 [KR] |
|
|
10-2017-0032630 |
|
Current U.S.
Class: |
1/1 |
Current CPC
Class: |
C22C
1/02 (20130101); C22C 38/58 (20130101); C22C
19/05 (20130101); C22C 30/00 (20130101); C22C
38/46 (20130101) |
Current International
Class: |
C22C
1/02 (20060101); C22C 38/58 (20060101); C22C
38/46 (20060101); C22C 19/05 (20060101); C22C
30/00 (20060101) |
References Cited
[Referenced By]
U.S. Patent Documents
Foreign Patent Documents
|
|
|
|
|
|
|
102787267 |
|
Nov 2012 |
|
CN |
|
2002-173732 |
|
Jun 2002 |
|
JP |
|
2010070814 |
|
Apr 2010 |
|
JP |
|
2016-023352 |
|
Feb 2016 |
|
JP |
|
10-2009-0030198 |
|
Mar 2009 |
|
KR |
|
10-2016-0014130 |
|
Feb 2016 |
|
KR |
|
WO-2016013498 |
|
Jan 2016 |
|
WO |
|
Other References
Stepanov; N.D., et al. "Effect of V content on microstructure and
mechanical properties of the CoCrFeMnNiVx high entropy alloys,"
Jan. 8, 2015, Journal of Alloys and Compounds vol. 628, p. 170-185
(Year: 2015). cited by examiner.
|
Primary Examiner: Zimmer; Anthony J
Assistant Examiner: Mazzola; Dean
Attorney, Agent or Firm: Lex IP Meister, PLLC
Claims
The invention claimed is:
1. A high-entropy alloy consisting of: Cr: 3-18 at%; Fe: 3-60 at%;
Mn: 3-40 at%; Ni: 20-80 at%; V: 3-12 at%; and unavoidable
impurities, wherein the ratio of the V content to the Ni content
(V/Ni) is 0.5 or less, and the alloy is a single phase of a face
centered cubic structure.
2. The high-entropy alloy of claim 1, wherein the sum of the Fe
content and the Mn content is less than 50 at%.
3. The high-entropy alloy of claim 1, wherein the alloy has tensile
strength of 1000 MPa or greater and elongation of 30% or greater at
an ultra-low temperature (77K).
4. The high-entropy alloy of claim 1, wherein the alloy has tensile
strength of 1000 MPa or greater and elongation of 60% or greater at
an ultra-low temperature (77K).
5. The high-entropy alloy of claim 1, wherein the alloy has tensile
strength of 800 MPa or greater and elongation of 30% or greater at
room temperature (298K).
Description
TECHNICAL FIELD
The present invention relates to a high-entropy alloy, which is
designed using thermodynamic calculations among computational
simulation techniques, and more particularly to, a
Cr--Fe--Mn--Ni--V-based high-entropy alloy having excellent low
temperature tensile strength and elongation by setting up an alloy
composition region having a single-phase microstructure of a face
centered cubic (FCC) at 700.degree. C. or higher through
thermodynamic calculations, and by allowing the FCC single-phase
microstructure to be obtained at room temperature and an ultra-low
temperature when quenching after heat treatment at 700.degree. C.
or higher is performed.
BACKGROUND ART
A high-entropy alloy (HEA) is a multi-element alloy composed of 5
or more elements, and is a new material of a new concept, which is
composed of a face centered cubic (FCC) single phase or a body
centered cubic (BCC) single phase and has excellent ductility
without generating an intermetallic phase due to a high mixing
entropy even through it is a high alloy system.
It has been reported in academic circles in 2004 under the name of
High Entropy Alloy (HEA) that a single phase is obtained without an
intermediate phase when five or more elements are alloyed with a
similar ratio without a main element, and recently, there is an
explosion of related research due to the sudden interest.
The reason why this particular atomic arrangement structure
appears, and the characteristics thereof are not clear. However,
the excellent chemical and mechanical properties of such structure
have been reported, and an FCC single phase CoCrFeMnNi high-entropy
alloy is reported to have a high yield and tensile strength due to
the expression of a twin in a nano unit at a low temperature, and
to have the highest toughness when compared with materials reported
so far.
A high-entropy alloy having a face centered cubic (FCC) structure
has not only excellent fracture toughness at an ultra-low
temperature but also excellent corrosion resistance, and excellent
mechanical properties such as high strength and high ductility, so
that the development thereof as a material for an ultra-low
temperature is being facilitated.
Meanwhile, Korean Patent Laid-Open Publication No. 2016-0014130
discloses a high-entropy alloy such as
Ti.sub.16.6Zr.sub.16.6Hf.sub.16.6Ni.sub.16.6Cu.sub.16.6Co.sub.17,
and
Ti.sub.16.6Zr.sub.16.6Hf.sub.16.6Ni.sub.16.6Cu.sub.16.6Nb.sub.17
both of which can be used as a heat resistant material, and
Japanese Patent Laid-Open Publication No. 2002-173732 discloses a
highly-entropy alloy which has Cu--Ti--V--Fe--Ni--Zr as a main
element and has high hardness and excellent corrosion
resistance.
As such, various high-entropy alloys are being developed, and in
order to expand the application area of high-entropy alloys, it is
required to develop a high-entropy alloy having various properties
while reducing manufacturing costs thereof.
DISCLOSURE OF THE INVENTION
Technical Problem
The purpose of the present invention is to provide a
Cr--Fe--Mn--Ni--V-based high-entropy alloy which has an FCC single
phase structure at room temperature and at an ultra-low temperature
and having low temperature tensile strength and low temperature
elongation properties which is capable of being suitably used at an
ultra-low temperature.
Technical Solution
An aspect of the present invention to achieve the above mentioned
purpose provides a high-entropy alloy including Cr: 3-18 at %, Fe:
3-60 at %, Mn: 3-40 at %, Ni: 20-80 at %, V: 3-12 at %, and
unavoidable impurities, wherein the ratio of the V content to the
Ni content (V/Ni) is 0.5 or less.
An alloy having such a composition is composed of a single phase of
FCC without generating an intermediate phase, and exhibits more
excellent tensile strength and elongation at an ultra-low
temperature (77K) than at room temperature (298K).
Advantageous Effects
A new high-entropy alloy provided by the present invention has
improved tensile strength and elongation at an ultra-low
temperature rather than at room temperature, and therefore, is
particularly useful as a structural material used in an extreme
environment such as an ultra-low temperature environment.
A high-entropy alloy according to the present invention may obtain
a strengthening effect more easily than an existing material by
adding vanadium (V) having a different nearest neighbor atomic
distance from those of other elements. In addition, by
appropriately controlling the content of the other four elements
according to the content of vanadium (V), the generation of a sigma
phase is suppressed and an FCC single phase is implemented so that
it is possible to obtain mechanical properties equal to or higher
than those of a conventional high-entropy alloy without performing
a strictly controlled heat treatment process.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 shows phase equilibrium information at 700.degree. C. an
alloy containing 15 at % of chromium (Cr) and 10 at % of vanadium
(V) according to mole fractions of iron (Fe), manganese (Mn), and
nickel (Ni) which constitute the remainder of the alloy.
FIG. 2 shows change in equilibrium phase according to the
temperature for an alloy having a composition represented by a star
(.star-solid.) in FIG. 1.
FIG. 3 shows phase equilibrium information at 700.degree. C.
according to mole fractions of remaining iron (Fe), manganese (Mn),
and nickel (Ni) of an alloy containing 10 at % of chromium (Cr) and
10 at % of vanadium (V).
FIG. 4 shows change in equilibrium phase according to the
temperature for an alloy having a composition represented by a star
(.star-solid.) in FIG. 3.
FIG. 5 shows phase equilibrium information at 700.degree. C. of an
alloy containing 30 at % of iron (Fe) and 20 at % of manganese (Mn)
according to mole fractions of chromium (Cr), nickel (Ni), and
vanadium (V) which constitute the remainder of the alloy.
FIG. 6 shows change in equilibrium phase according to the
temperature for an alloy having a composition represented by a star
(.star-solid.) in FIG. 5.
FIG. 7 shows phase diagrams of binary alloy systems composed of two
elements among five elements of chromium (Cr), iron (Fe), manganese
(Mn), nickel (Ni), and vanadium (V).
FIG. 8 is a photograph of an EBSD inverse pole figure (IPF) map of
a high entropy alloy plate material manufactured according to
Example 1 and Example 3 of the present invention.
FIG. 9 shows results of an X-ray diffraction analysis of a
high-entropy alloy plate material manufactured according to Example
1 and Example 3 of the present invention.
FIG. 10 is a photograph of an EBSD phase map of a high-entropy
alloy plate material manufactured according to Example 1 and
Example 3 of the present invention.
FIG. 11 shows results of a room temperature (298K) tensile test of
a high-entropy alloy manufactured according to Example 1 and
Example 3 of the present invention.
FIG. 12 shows results of an ultra-low temperature (77K) tensile
test of a high-entropy alloy manufactured according to Example 1
and Example 3 of the present invention.
FIG. 13 shows results of an ultra-high temperature (77K) tensile
test of a high-entropy alloy manufactured according to Example 2 of
the present invention.
BEST MODE FOR CARRYING OUT THE INVENTION
Hereinafter, the configuration and the operation of embodiments of
the present invention will be described with reference to the
accompanying drawings. In describing the present invention, a
detailed description of related known functions and configurations
will be omitted when it may unnecessarily make the gist of the
present invention obscure. Also, when certain portion is referred
to "include" a certain element, it is understood that it may
further include other elements, not excluding the other elements,
unless specifically stated otherwise.
FIG. 1 shows phase equilibrium information at 700.degree. C. of an
alloy containing 15 at % of chromium (Cr) and 10 at % of vanadium
(V) according to mole fractions of iron (Fe), manganese (Mn), and
nickel (Ni) which constitute the remainder of the alloy.
Regions 1 and 2 of FIG. 1 represent regions in which an FCC single
phase is maintained at 700.degree. C. or lower, and the remaining
regions show regions in which two-phase or three-phase equilibrium
are maintained. Alloys having a composition belonging to the Region
2 of FIG. 1 maintain the FCC single phase from a melting
temperature down to 700.degree. C. or lower, to 500.degree. C. At
this time, a composition located at a boundary portion of a
two-phase equilibrium region maintains the FCC single phase down to
700.degree. C. in calculation.
A line between the Region 1 and the Region 2 is a line representing
a boundary between the FCC single phase region and the two-phase
equilibrium region calculated at 500.degree. C. Alloys having a
composition belonging to the Region 1 of FIG. 1 maintain the FCC
single phase from a melting temperature to 500.degree. C. or lower.
A composition located at a boundary between the Region 1 and the
Region 2 maintains the FCC single phase down to 500.degree. C. in
calculation.
That is, FIG. 1 means that alloys composed of 5 elements or less
including 15 at % of chromium (Cr), 10 at % of vanadium (V), 0-48
at % of iron (Fe), 0-25 at % of manganese (Mn), and 27-75 at % of
nickel (Ni) all maintain the FCC single phase from the melting
temperature down to 700.degree. C. or lower.
FIG. 2 shows change in equilibrium phase according to the
temperature for an alloy having a composition represented by a star
(.star-solid.) in FIG. 1. An alloy having the composition
represented by the star (.star-solid.) is a composition located at
a boundary between the Region 2 and the two-phase equilibrium
region in FIG. 1, thereby forming an FCC single phase region from
the melting temperature down to 700.degree. C.
FIG. 3 shows phase equilibrium information at 700.degree. C. of an
alloy containing 10 at % of chromium (Cr) and 10 at % of vanadium
(V) according to mole fractions of iron (Fe), manganese (Mn), and
nickel (Ni) which constitute the remainder of the alloy.
FIG. 3 means that alloys composed of 5 elements or less including
10 at % of chromium (Cr), 10 at % of vanadium (V), 0-56 at % of
iron (Fe), 0-41 at % of manganese (Mn), and 23-80 at % of nickel
(Ni) all maintain the FCC single phase from the melting temperature
down to 700.degree. C. or lower.
FIG. 4 shows change in equilibrium phase according to the
temperature for an alloy having a composition represented by a star
(.star-solid.) in FIG. 3.
FIG. 5 shows phase equilibrium information at 700.degree. C. of an
alloy containing 30 at % of iron (Fe) and 20 at % of manganese (Mn)
according to mole fractions of chromium (Cr), nickel (Ni), and
vanadium (V) which constitute the remainder of the alloy.
FIG. 5 means that alloys composed of 5 elements or less including
30 at % of iron (Fe), 20 at % of manganese (Mn), 0.about.18 at % of
chromium (Cr), 28-50 at % of nickel (Ni), 0-18 at % of vanadium (V)
all maintain the FCC single phase from the melting temperature down
to 700.degree. C. or lower.
FIG. 6 shows change in equilibrium phase according to the
temperature for an alloy having a composition represented by a star
(.star-solid.) in FIG. 5.
FIG. 7 shows phase diagrams of binary alloy systems composed of two
elements among five elements of chromium (Cr), iron (Fe), manganese
(Mn), nickel (Ni), and vanadium (V).
In FIG. 7, the FCC single-phase region and the sigma phase region
which deteriorates mechanical properties are displayed in dark
color. Six binary alloy systems not including vanadium (V) have a
small sigma phase region and a widely distributed FCC single phase
region. On the other hand, four binary alloy systems including
vanadium (V) have a relatively wide sigma phase region.
Particularly, in the cases of a nickel (Ni)-vanadium (V) binary
alloy system, the sigma phase region is distributed to a high
temperature at which a liquid phase is stable. However, in the
nickel (Ni)-vanadium (V) alloy system phase diagram, the sigma
phase mainly appears in a section in which the ratio of vanadium
(V) content to nickel (Ni) content (V/Ni) is high, and a wide FCC
single phase appears in a section in which the ratio of vanadium
(V) content to nickel (Ni) content (V/Ni) is low.
FIG. 7 means that if the ratio of V content to Ni content (V/Ni) is
lowered, it is possible to design a high-entropy alloy composed of
the FCC single phase.
From the thermodynamic information shown in FIG. 1, FIG. 3, FIG. 5
and FIG. 7, inventors of the present invention have derived a
high-entropy alloy composed of an FCC single phase and having
excellent low temperature properties, the alloy including 3-18 at %
of Cr, 3-60 at % of Fe, 3-40 at % of Mn, 20-80 at % of Ni, 3-12 at
% of V, and unavoidable impurities, wherein the ratio of the V
content to the Ni content (V/Ni) is 0.5 or less.
When the content of Cr is less than 3 at %, it is disadvantageous
to mechanical properties of an alloy such as corrosion resistance,
and when the content of Cr is greater than 18 at %, the possibility
an intermediate phase being generated is increased. Therefore, the
content of the Cr is preferably 3-18 at %. When phase stability and
mechanical properties are considered, the content of the Cr is more
preferably 7-18 at %.
When the content of Fe is less than 3 at %, it is disadvantageous
to manufacturing costs, and when the content of Fe is greater than
60 at %, the phase becomes unstable. Therefore, the content of the
Fe is preferably 3-60 at %. When phase stability and mechanical
properties are considered, the content of the Fe is more preferably
18-35 at %.
When the content of Mn is less than 3 at %, it is disadvantageous
to manufacturing costs, and when the content of Mn is greater than
40 at %, the phase becomes unstable and there is a possibility of
an oxide is formed during a manufacturing process. Therefore, the
content of the Mn is preferably 3-40 at %. When phase stability and
mechanical properties are considered, the content of the Mn is more
preferably 10-25 at %.
When the content of Ni is less than 20 at %, the phase becomes
unstable, and when the content of Ni is greater than 80 at %, it is
disadvantageous to manufacturing costs. Therefore, the content of
the Ni is preferably 20-80 at %. When phase stability and
mechanical properties are considered, the content of the Ni is more
preferably 25-45 at %.
When the content of V is less than 3 at %, it is difficult to
obtain a strengthening effect and when the content of V is greater
than 12 at %, the possibility of an intermediate phase being
generated is increased. Therefore, the content of the V is 3-12
atom % is preferable. When phase stability, mechanical properties,
and manufacturing costs are considered, the content of the V is
more preferably 5-12 at %.
In addition, in order to stably implement an FCC single phase
structure, it is preferable that the ratio of the V content to the
Ni content (V/Ni) is 0.5 or less.
It is preferable to maintain the composition ranges of an alloy
since it becomes difficult to obtain a solid solution having an FCC
single phase when the composition ranges deviate from respective
composition constituting the alloy.
In addition, in the high-entropy alloy, when the content of Ni is
30 at % or greater, optimal properties are exhibited. Therefore, it
is preferable that the sum of the Fe and the Mn is 50 at % or
less.
In addition, in the aspect of obtaining a high-entropy alloy having
excellent mechanical properties and stability, it is more
preferable that the composition of each component constituting the
high-entropy alloy is 7-18 at % of Cr, 18-35 at % of Fe, 10-25 at %
of Mn, 25-45 at % of Ni, 5-12 at % of V, wherein the ratio of the V
content to the Ni content (V/Ni) is 0.5 or less.
In addition, the high-entropy alloy may have tensile strength of
1000 MPa or greater and elongation of 30% or greater at an
ultra-low temperature (77K).
In addition, the high-entropy alloy may have tensile strength of
1000 MPa or greater and elongation of 60% or greater at an
ultra-low temperature (77K).
In addition, the high-entropy alloy may have tensile strength of
800 MPa or greater and elongation of 30% or greater at room
temperature (298K).
Hereinafter, the present invention will be described in more detail
based on preferred embodiments of the present invention, but the
present invention should not be construed as being limited to the
preferred embodiments of the present invention.
EXAMPLE 1
Manufacturing a High-Entropy Alloy
Table 1 below shows three compositions selected for manufacturing
an alloy of a region calculated through the thermodynamic review
described above.
TABLE-US-00001 TABLE 1 Alloy Ingot composition (at %) No. Cr Fe Mn
Ni V 1 15 22 13 40 10 2 10 30 20 30 10 3 15 30 20 30 5
Cr, Fe, Mn, Ni, and V of 99.9% or greater of high purity were
prepared so as to have the composition shown in Table 1, and an
alloy was melted at a temperature of 1500.degree. C. or higher
using a vacuum induction melting furnace to prepare an ingot by a
known method.
EXAMPLE 1
No. 1 alloy ingot was maintained in an FCC single phase region at
1000.degree. C. for 2 hours to homogenize the structure thereof,
and then the homogenized ingot was pickled to remove impurities and
an oxide layer on the surface thereof.
The pickled ingot was cold-rolled at a reduction ratio of 75% to
produce a cold rolled-plate.
The cold-rolled plate as such was subjected to heat treatment
(800.degree. C., 2 hours) in the FCC single phase region to remove
residual stress, and crystal grains were completely recrystallized
and then water-cooled to manufacture a high-entropy alloy plate
material.
EXAMPLE 2
No. 1 alloy ingot was maintained in an FCC single phase region at
1100.degree. C. for 6 hours to homogenize the structure thereof,
and then the homogenized ingot was pickled to remove impurities and
an oxide layer on the surface thereof.
The pickled ingot was cold-rolled at a reduction ratio of 75% to
produce a cold rolled-plate.
Thereafter, the cold-rolled plate was subjected to heat treatment
(800.degree. C., 2 hours) in the FCC single phase region to remove
residual stress, and crystal grains were completely recrystallized
and then water-cooled to manufacture a high-entropy alloy plate
material.
That is, the high-entropy alloy plate material manufactured
according to Example 2 has the same composition as in Example 1
except that only heat treatment conditions are different.
EXAMPLE 3
No. 2 alloy ingot was manufactured into a high-entropy alloy plate
material through the same manufacturing process as in Example
1.
No. 3 alloy ingot of Table 1 above was not manufactured into a
high-entropy alloy plate material to evaluate microstructure and
mechanical properties thereof. However, as shown in FIG. 6, it can
be seen that it is a composition capable of generating an FCC
single phase at room temperature (298K) and at an ultra-low
temperature (77K) when quenching after heat treatment in the FCC
single phase region (800.degree. C. or higher) is performed.
Microstructure
The microstructure of a high-entropy alloy manufactured as
described above was analyzed using a scanning electron microscope,
an X-ray diffraction analyzer, and an EBSD.
FIG. 8 is a photograph of an EBSD inverse pole figure (IPF) map of
a high-entropy alloy manufactured according to Example 1 and
Example 3.
It is possible to measure the size of the crystal grains from the
map, and the two alloys which were subjected to cold rolling at the
reduction ratio of 75% and recrystallization heat treatment have a
mean crystal grain size of 5.4-7.4 .mu.m. Crystal phases have a
polycrystalline shape, and the size thereof is relatively uniform
regardless of the composition of the alloy.
FIG. 9 shows results of an X-ray diffraction analysis of a
high-entropy alloy plate manufactured according to Example 1 and
Example 3 of the present invention. The two alloys exhibit the same
peak, and according to the analysis result thereof, it was
confirmed that the peak corresponds to an FCC structure.
FIG. 10 is a photograph of an EBSD phase map of a high-entropy
alloy plate material manufactured according to Example 1 and
Example 3. The EBSD phase map displays each phase in different
colors when two or more different phases are in the microstructure.
As confirmed in FIG. 10, alloys according to Example 1 and Example
3 are all represented in the same single color, which means that
the microstructure of the alloys is composed of an FCC single
phase, and a second phase such as a sigma phase which deteriorates
mechanical properties is not generated.
Evaluation of Mechanical Properties at Room Temperature and at an
Ultra-Low Temperature
Tensile properties of a high-entropy alloy plate material
manufactured as described above were evaluated at room temperature
(298K) through a tensile tester. FIG. 11 and Table 2 show the
results.
TABLE-US-00002 TABLE 2 Room temperature (298 K) YS (MPa) UTS (MPa)
El. (%) Example 1 460 815 45.2 Example 2 503 842 35.2
As shown in Table 2, the high-entropy alloy plate materials
according to Example 1 and Example 3 of the present invention
exhibit excellent tensile properties at room temperature (298K)
having a yield strength of 460-503 MPa, tensile strength of 815-842
MPa, and elongation of 35-45%.
FIGS. 12 and 13, and Table 3 below show results of evaluating
tensile properties at an ultra-low temperature (77K) using an
ultra-low temperature chamber and a tensile tester.
* * * * *